California Department of Transportation
 

MAP-21(Moving Ahead for Progress in the 21st Century)

Enhanced National Highway System

Map: Go to Caltrans Earth, then click on the left column Highways/Map-21 NHS.

As per the new federal authorization MAP-21, starting October 1, 2012 the existing National Highway System (NHS) has been expanded to include all Principal Arterials (i.e. Functional Classifications 1,2 and 3) to the new Enhanced NHS.

Map-21 Legislation - [§1104; 23 USC 103]:

The National Highway System (NHS) consists of the following:

  • The NHS depicted on the map submitted by the Secretary of Transportation to Congress with the report entitled 'Pulling Together: The NHS and its Connections to Major Intermodal Terminals' and dated May 24, 1996, and modifications approved by the Secretary before the date of enactment of the MAP-21.
  • Other urban and rural principal arterial routes, and border crossings on those routes, that were not included on the NHS before the date of enactment of the MAP-21.
  • Other connector highways (including toll facilities) that were not included in the NHS before the date of enactment of the MAP-21 but that provide motor vehicle access between arterial routes on the NHS and a major intermodal transportation facility.
  • A strategic highway network (STRAHNET) that consists of a network of highways that are important to the US strategic defense policy, that provide defense access, continuity, and emergency capabilities for the movement of personnel, materials, and equipment in both peacetime and wartime, and that were not included on the NHS before the date of enactment of the MAP-21. May include highways on or off the Interstate System; and shall be designated by the Secretary, in consultation with appropriate Federal agencies and the States.
  • Major STRAHNET connectors that consist of highways that provide motor vehicle access between major military installations and highways that are part of the Strahnet but were not included on the NHS before the date of enactment of the MAP-21; and shall be designated by the Secretary, in consultation with appropriate Federal agencies and the States.

MAP-21 Legislation:  http://www.fhwa.dot.gov/map21/legislation.cfm 

Enhanced NHS Summary:

Under MAP-21, the Enhanced NHS is composed of approximately 160,000 miles of rural and urban roads nationwide serving major population centers, international border crossings, intermodal transportation facilities, and major travel destinations. It includes:

  • The Interstate System.
  • All principal arterials (including those not previously designated as part of the NHS) and border crossings on those routes.
  • Intermodal connectors -- highways that provide motor vehicle access between the NHS and major intermodal transportation facilities.
  • STRAHNET -- the network of highways important to U.S. strategic defense.
  • STRAHNET connectors to major military installations.
  • FHWA's Q & A

NHS Database:

Summary of NHS mileage

Map-21 State Highway NHS

Map-21 Non-State Highway NHS

For specific information regarding NHS data, please contact Rose Cuellar.

Contact:

Navneet Singh (Branch Chief) at (916) 654-6585 or navneet.singh@dot.ca.gov.

Rose Cuellar (Staff) at (916) 654-2927 or rose.cuellar@dot.ca.gov